1. Field of the Invention
This invention relates generally to a system and method for predicting the driving range of an electrical vehicle and, more particularly, to a system and method for predicting the driving range of a plug-in battery only electric vehicle that considers the power draw from the vehicle's heating, ventilation and cooling (HVAC) system.
2. Discussion of the Related Art
Electric vehicles are becoming more and more prevalent. These vehicles include hybrid vehicles, such as the extended range electric vehicles (EREV) that combine a battery and a main power source, such as an internal combustion engine, fuel cell systems, etc., and electric only vehicles, such as the battery electric vehicles (BEV). All of these types of electric vehicles employ a high voltage battery that includes a number of battery cells. These batteries can be different battery types, such as lithium ion, nickel metal hydride, lead acid, etc. A typical high voltage battery system for an electric vehicle may include a large number of battery cells or modules to meet the vehicle power and energy requirements. The battery system can include individual battery modules where each battery module may include a certain number of battery cells, such as twelve cells. The individual battery cells may be electrically coupled in series, or a series of cells may be electrically coupled in parallel, where a number of cells in the module are connected in series and each module is electrically coupled to the other modules in parallel. Different vehicle designs include different battery designs that employ various trade-offs and advantages for a particular application.
For plug-in electric vehicles (EV) capable of driving on battery power for extended distances, the remaining vehicle travel distance that is able to be provided by the battery is crucial information to be displayed to the driver and necessary for vehicles that run on battery power only. Currently, systems and algorithms do exist for determining this distance traveled value. However, those known systems are somewhat limited in that they do not consider power draw by the vehicles heating, ventilation and cooling (HVAC) system or are able to learn a driver's driving habits over time to calculate the distance.